If the data set is large enough and the data alternately increases and decreases, fluctuates - go up and down, the best type of trend line is polynomial. However, keep in mind that the polynomial trend is intended to describe the current data set and calculate the values within it. It is not intended for making predictions at all. See more about the different types of trendlines you can create in Excel:

If you have data with only positive values that show a steady increase or decrease with a fixed rate of growth or decline, use the power trendline. See more about the different types of trendlines you can create in Excel:

If the data is strictly positive and increases or decreases rapidly with a constantly increasing rate, the best type of trend line is exponential. See more about the different types of trendlines you can create in Excel:

Dynamic, dependable, conditional, or calculated drop-down list in Excel implies that the contents of the drop-down list for the current cell should depend on values in the other cell and change dynamically when the value of the controlling cell changes.

In addition to searching for and replacing text, you can search for and replace Word's special characters, such as paragraph and tab marks.

Every workbook uses a palette of 56 colors, but you can change the palette for the current workbook or even change the default colors for new workbooks.

If you want to stress the cyclic nature in a diagram, schema or chart will be useful to create circling arrows or arrows in a circle and use them for the background picture.
PowerPoint proposes several predefined features for circular diagrams, such as SmartArt, and you can find plenty of them on the Internet. However, it is easy to create your own diagram to give your presentation a professional look.

The new PowerPoint Designer feature automatically generates design ideas on the new Design Ideas pane. By default, this pane appears on the right side of the slide and can be very useful for creative users:

When you create the process flow chart, process map, business flow diagram, or data flow diagrams and UML activity diagrams, you often need to add some text or labels to the connectors. Unlike many other free and commercial diagram drawing packages, Microsoft Office shapes provide extremely rich text formatting features.

Manual data entry into spreadsheets and especially entering data into text cells leads to many errors. Excel data validation tools allow you to reduce the inaccuracy of Excel data entry by restricting the set of possible values to a pre-defined list. Users can select the item from a drop-down list with few choices instead of typing text into the data entry form template.